The general objective of the proposed research is to investigate order within the cell nucleus. The first objective is to determine whether or not there is a specific arrangement of non-homologous chromosomes. This will be done by using the Giemsa barring technique to differentially stain the haploid chromosomes of Ornithogalum virens. Attachment of chromosome ends to the nuclear membrane in mitotic prophase nuclei will be examined with the scanning electron microscope. The nature of the non-homologous attachments and the means of attachment of the ends to the nuclear membrane will be examined through enzymatic digestion studies and autoradiograms. Association of homologous chromosomes will be examined in a series of studies on somatic crossing over, an event which depends on close somatic association of homologous chromosomes. This study will be conducted primarily with soybeans heterozygous for a nuclear gene for chlorophyll synthesis. The study will involve both cytological examination of meristematic tissue for "somatic chiasmata" and an examination of the leaves with twin spots (a result of segregation of Y11 Y11 and y11 y11). The effect of an asynaptic gene on somatic crossing over will also be examined for further indication of a "meiotic gene" having its first effect on somatic cells. Fertilization, or more specifically karyogamy will be examined as the possible stage in the life cycle where recognition of homologous chromosomes occur.